Eric, you are totally correct. Power assist (vacuum assist), and this
"miracle fluid" that has been mentioned (if it worked), are merely
methods for reducing pedal effort by multiplying the effect of your foot
on the brake pedal. They have no effect on stopping distance, unless the
driver is personally so feeble in the leg department that he/she is
unable to apply enough effort to the brake pedal to achieve minimum
stopping distance (just short of lock up). Any healthy MGB brake system
is capable of locking up the front wheels -- no further improvements in
stopping distance can be easily made short of stickier tires, weight
redistribution, or downforce. However, ventilated or cross-drilled disk
brake systems can have other benefits such as fade resistance or improved
wet-weather braking. For racing use a more robust overall system could be
helpful. A properly proportioned rear disk system might actually reduce
stopping distance, I would speculate, by controlling rear brake lockup,
but ??.
Anyway, I still haven't figured out what Tab is looking for in terms of
brake improvements: minimizing stopping distance? less fade? pedal
"feel"? or just the "cool" factor?
Some practical changes that might improve subjective brake performance
would be semi-metallic pads (less squeal and fade), and the braided
stainless/teflon brake hoses (less expansion under pressure, for a
stiffer pedal feel).
Eric had this to say:
>Yep, I am confused about this 'braking power', as displayed the other
>day, when I press down on my brake pedal, the 'braking power' or rather
>the 'stopping power' is up to me. Either I can judge the 'point of no
>return' grip between my tyres and the road correctly and therefore stop
>quickly, or I can misjudge this and lock up the wheels, sliding to a
>halt further down the road (in a foul-smelling cloud of brakes and
>rubber).
>
>My brakes easily stop my wheels going around but this has no relation to
>how quickly the car stops moving in a forward (or rearward... or
>sidward) direction.
>
>Or am I missing something here?
>
>
>Eric
>
--
Max Heim
'66 MGB GHN3L76149
If you're near Mountain View, CA,
it's the red one with the silver bootlid.
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